Answer:
The solution would need 13.9 g of KCl
Explanation:
0.75 m, means molal concentration
0.75 moles in 1 kg of solvent.
Let's think as an aqueous solution.
250 mL = 250 g, cause water density (1g/mL)
1000 g have 0.75 moles of solute
250 g will have (0.75 . 250)/1000 = 0.1875 moles of KCl
Let's convert that moles in mass (mol . molar mass)
0.1875 m . 74.55 g/m = 13.9 g
 
        
             
        
        
        
Answer:
5
Explanation:
To balance the hydrogen atoms, we check the number of hydrogen on the left side, this is equal to the 10 hydrogen atoms we have in the alkanol.
Now, on the right hand side, we can see we only have two hydrogen atoms in the water molecule. Now, to make equal the number of hydrogen atoms on both sides, we simply multiply the number of hydrogen there by 5 to make it 10 too
 
        
             
        
        
        
The amount of liquid is measured in L. As the unit Lm is only used when measuring the mass liquid fraction. 
 
        
             
        
        
        
The option that would best contrast the real and the model atoms is letter "D. model of an atom is not as small as an actual atom". The size of an atom is said to be no more than 0.1 to 0.5 nanometers. The models are used to proper illustrate the atom's physical attributes. That is why, it needs to be bigger in size.